Johann Friedrich Tolksdorf

Potential of palaeosols, sediments and archaeological features to reconstruct Late Glacial fire regimes in northern Central Europe – case study Grabow site and overview

Late Glacial fires in Northern Germany are well known from different geoarchives such as palaeosols, (limnic) sediments and archaeological sites. This has evoked the question if the fire regime during the Allerod and Younger Dryas was driven exclusively by natural agents (temperature, precipitation, vegetation pattern) or was – at least to some extent – a result of anthropogenic burning. We contribute to this question by examining on-site and off-site archives in the Jeetzel valley at the Late Palaeolithic site Grabow 15 (N-Germany). The spatial analysis of the charcoal distribution and biomarkers (“black carbon”) in an on-site test area enabled a detailed reconstruction of human burning activities during the early Allerod. A determination of the charred wood taxa allowed a reconstruction of the local vegetation pattern during the time of human occupation. The evidence of man-made fire was compared to the general occurrence of charcoal particles in two palaeochannels that provided archives for palynological and sedimentological analysis for the time span from the Allerod to the early Holocene. Based on the reconstructed local vegetation patterns, human occupation phases and water levels we conclude that human presence during the early Allerod must have increased the input of charcoal and biomarkers into the local sediments. During the Younger Dryas no human contribution to the local charcoal influx was detected. We concluded that future studies must considerate the very local impact of man-made fires in much greater detail.

Ivory or bone? A report on practical experience determining material from the Mesolithic site Klein Breese (Northern Germany)

As recent studies have provided the first proof of the secondary use of fossil ivory in Northern Germany during the Late Palaeolithic (Gramsch et al. J Archaeol Sci 40:2458–2463, 2013), a number of compact biological fragments excavated from a Mesolithic site were studied to identify the material and the species from which they derived, with a special focus on possibly identifying ivory. Detailed analysis of the sample surfaces by optical microscopy and SEM showed alteration due to weathering and thereby made detailed morphological studies without further preparation difficult. Subsequent chemical analyses were based on the most common method, Raman spectroscopy, and the measurement of the δ13C value; they did not contradict the hypothesis of ivory as the raw material. However, the results were not able to provide a positive identification of the material; hence, histological studies were performed using thin sections and micro-X-ray tomography. The result clearly provided evidence that the fragments were derived from cortical bone and not from ivory. By presenting our experiences and difficulties in the interpretation of the results, we hope to provide help for archaeological researchers in choosing the most suitable methods in comparable future studies.

Beaver (Castor fiber) Activity in an Archaeological Context: A Mid-Holocene Beaver Burrow Feature and a Late-Holocene Ecofact at the Late Palaeolithic Grabow Site, Northern Germany

ABSTRACT Bioturbation and intrusive ecofacts are major concerns for the analysis of archaeological sites in wetland environments. Post-sedimentary influence of beavers (Castor fiber) is described for a well dated Late Palaeolithic archaeological record situated in a floodplain in Northern Germany. An extensive burrow system was documented and analysed according to its spatial dimensions and sedimentological properties; it was interpreted to be the result of beaver activity. Palynological analyses proved a Mid-Holocene origin of the infill material and helped in understanding the history of site formation. In addition, a pointed piece of wood was examined and identified as ecofact, which had been gnawed by a small rodent, possibly Arvicola amphibius (water vole). Our study thus illustrates the potential complexity of post-sedimentary site-alteration, describes the sub-surface morphology of a burrow system in a wetland context and documents risks for erroneous archaeological interpretation.